Zhong Yi Optics has just unveiled their latest lens, the Mitakon Speedmaster 65mm f/1.4. This is a medium format lens designed specifically for Fujifilm GF mount cameras like the GFX 50s.
As standard focal length lenses go, Fujifilm currently only offers the GF 63mm f/2.8. This is a fantastic lens; however, the aperture isn't as wide as many photographers may have preferred. The new Speedmaster lens has the ability to gather four times as much light (depending on the T-stop) and produce images with noticeably shallower depth of field.
Portrait photographers are probably going to love this lens because of how it will isolate subjects when shooting wide open. The lens can focus as close as 70 cm, which isn't the closest; however, the depth of field will be more manageable due to the distance. This lens is manual focus only and does not have any electronic contacts to communicate with the camera. This may make things tricky to shoot with wide open, although the GFX does offer focus peaking.
The 65mm focal length on the GFX will be somewhat similar to a 50mm lens on a full frame camera. One of my main complaints about the GFX was that there weren't any wide aperture lenses around f/1.4. This meant that shooting in low light was somewhat tricky and you'd almost always have to bump up ISO and introduce noise into the images. Due to that, I'm very happy to see ZY Optics is now offering an f/1.4 lens for the GFX.
When it comes to sharpness and detail, there's a good chance it's probably not quite as good as Fuji lenses when shot wide open. Having said that, from what I've seen online, stopping the lens down does produce some very sharp and detailed results.
Finally, the lens has 11 elements in 7 groups, with 9 aperture blades and a retractable hood. The lens also weighs more than (2 lbs) 1 kg, so it's obviously not the lightest.
Images by Jonas Rask courtesy of ZY Optics.